{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-40347", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.187Z", "datePublished": "2025-12-16T13:30:21.539Z", "dateUpdated": "2026-08-05T12:09:48.141Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:09:48.141Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: enetc: fix the deadlock of enetc_mdio_lock\n\nAfter applying the workaround for err050089, the LS1028A platform\nexperiences RCU stalls on RT kernel. This issue is caused by the\nrecursive acquisition of the read lock enetc_mdio_lock. Here list some\nof the call stacks identified under the enetc_poll path that may lead to\na deadlock:\n\nenetc_poll\n -> enetc_lock_mdio\n -> enetc_clean_rx_ring OR napi_complete_done\n -> napi_gro_receive\n -> enetc_start_xmit\n -> enetc_lock_mdio\n -> enetc_map_tx_buffs\n -> enetc_unlock_mdio\n -> enetc_unlock_mdio\n\nAfter enetc_poll acquires the read lock, a higher-priority writer attempts\nto acquire the lock, causing preemption. The writer detects that a\nread lock is already held and is scheduled out. However, readers under\nenetc_poll cannot acquire the read lock again because a writer is already\nwaiting, leading to a thread hang.\n\nCurrently, the deadlock is avoided by adjusting enetc_lock_mdio to prevent\nrecursive lock acquisition." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - The deadlock is driven from the enetc RX datapath (`enetc_poll` → `napi_gro_receive` → stack → `enetc_start_xmit`), reached purely by packets arriving on the Ethernet interface, including routed IP traffic from arbitrary remote networks. No L2 adjacency or local access is needed — a plain ICMP/TCP flow that elicits a reply or is forwarded suffices.\nAC:L - The attacker directly creates the recursive read-lock condition by sustaining inbound traffic that triggers a transmit from within the RX softirq, and the competing MDIO writer occurs many times per second from the periodic phylib/phylink state machine, so the collision is reached reliably within seconds and can be retried indefinitely.\nPR:N - The vulnerable path is the unauthenticated packet-receive path of the NIC driver; no credentials, capabilities, or local account are required — merely sending traffic to (or through) the affected interface is enough.\nUI:N - No victim action is needed; the deadlock arises from normal kernel-side packet processing and background PHY polling that run without any user involvement.\nS:U - The lock inversion hangs kernel threads within the same security authority as the affected kernel; no VM, IOMMU, or sandbox boundary is crossed.\nC:N - This is a pure lock-ordering/recursion defect with no memory corruption, out-of-bounds access, or exposure of kernel data to the attacker.\nI:N - No data is modified and no write primitive is produced; the failure mode is threads blocking on an rt_mutex-backed rwlock, not memory corruption.\nA:H - The recursive read-lock acquisition deadlocks the NAPI poll thread against a waiting MDIO writer, producing RCU stalls, hung tasks, and permanent loss of network processing on the interface — a remotely inducible, unrecoverable denial of service." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/freescale/enetc/enetc.c" ], "versions": [ { "version": "6d36ecdbc4410e61a0e02adc5d3abeee22a8ffd3", "lessThan": "a649161526736f48bcc592e3a412e5bcd7dd9e24", "status": "affected", "versionType": "git" }, { "version": "6d36ecdbc4410e61a0e02adc5d3abeee22a8ffd3", "lessThan": "2781ca82ce8cad263d80b617addb727e6a84c9e5", "status": "affected", "versionType": "git" }, { "version": "6d36ecdbc4410e61a0e02adc5d3abeee22a8ffd3", "lessThan": "1f92f5bd057a4fad9dab6af17963cdd21e5da6ed", "status": "affected", "versionType": "git" }, { "version": "6d36ecdbc4410e61a0e02adc5d3abeee22a8ffd3", "lessThan": "2e55a49dc3b2a6b23329e4fbbd8a5feb20e220aa", "status": "affected", "versionType": "git" }, { "version": "6d36ecdbc4410e61a0e02adc5d3abeee22a8ffd3", "lessThan": "50bd33f6b3922a6b760aa30d409cae891cec8fb5", "status": "affected", "versionType": "git" }, { "version": "bf9c564716a13dde6a990d3b02c27cd6e39608bf", "status": "affected", "versionType": "git" }, { "version": "ff966263f5f9fdf9740f03fed0762ce73c230a6a", "status": "affected", "versionType": "git" }, { "version": "5.10.24", "lessThan": "5.11", "status": "affected", "versionType": "semver" }, { "version": "5.11.7", "lessThan": "5.12", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/ethernet/freescale/enetc/enetc.c" ], "versions": [ { "version": "5.12", "status": "affected" }, { "version": "0", "lessThan": "5.12", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.175", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.115", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.56", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.17.6", "lessThanOrEqual": "6.17.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12", "versionEndExcluding": "6.1.175" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12", "versionEndExcluding": "6.6.115" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12", "versionEndExcluding": "6.12.56" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12", "versionEndExcluding": "6.17.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12", "versionEndExcluding": "6.18" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10.24" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11.7" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/a649161526736f48bcc592e3a412e5bcd7dd9e24" }, { "url": "https://git.kernel.org/stable/c/2781ca82ce8cad263d80b617addb727e6a84c9e5" }, { "url": "https://git.kernel.org/stable/c/1f92f5bd057a4fad9dab6af17963cdd21e5da6ed" }, { "url": "https://git.kernel.org/stable/c/2e55a49dc3b2a6b23329e4fbbd8a5feb20e220aa" }, { "url": "https://git.kernel.org/stable/c/50bd33f6b3922a6b760aa30d409cae891cec8fb5" } ], "title": "net: enetc: fix the deadlock of enetc_mdio_lock", "x_generator": { "engine": "bippy-1.2.0" } } } }